State health officials blamed lack of access to health care, along with lower vaccination rates and other chronic health problems -- but added that the real reasons are hard to determine.

Authorities are trying to get the word out that free vaccinations in public clinics are safe and effective, and "no one's going to ask about immigration status," the CDC's Dr. Felipe Lobelo told the AP. Even swine flu hospitalization rates among blacks and Hispanics are triple those of whites.

Sixty-seven people in Illinois have died of the H1N1 flu virus since April, and more than 2,100 people have been hospitalized.

Health officials warn there may be another surge in infection rates after students return to school following the holiday break.